1. Field of the Invention
The present invention relates to a printing apparatus that performs printing on a continuous sheet.
2. Description of the Related Art
A continuous sheet roll is used in printing a large number of prints, such as in lab printing. When producing a continuous sheet roll, from the viewpoint of improving manufacturing yield, a roll having a required length may be formed by joining ends of a plurality of continuous sheets whose lengths are less than the required length to each other with a joining material such as a splicing tape (hereafter referred to as “tape”). In the continuous sheet roll, splices (joints) joined to each other with a tape are randomly provided at more than one location.
In an apparatus discussed in Japanese Patent Laid-Open No. 2001-239715, control is performed so that printing is not performed on an area including the splice, that is, an unrecordable area, by detecting the position of the splice by detecting a tape using an optical sensor.
When printing, for example, a high-quality photographic image, a slight difference between the characteristics of sheets used (such as, sheet type, sheet quality, and sheet thickness) is manifested as a difference between print qualities. Therefore, if the characteristics of a leading sheet and a following sheet that are joined to each other at a splice of a continuous sheet differ from each other, images in front of and behind the splice have different qualities, such as different tones, gradations, and contrasts. A difference between print qualities of a plurality of pages of one printed material, such as a photographic album, causes a person to look at the printed material with an improper color tone, etc. Therefore, it is desirable for the print qualities of images which are successively printed on a continuous sheet be the same. Japanese Patent Laid-Open No. 2001-239715 does not acknowledge the existence of such a problem and does not discuss anything about a method of overcoming such a problem.
The present invention is carried out on the basis of an acknowledgement of the existence of the above-described problem. The present invention provides a technique of reducing differences between print qualities at portions in front of and behind a splice in performing printing on a continuous sheet having splices.